Volatilization of Selected Organic Compounds from Quiescent Water

Volatilization of selected organic compounds from water without agitation has been studied. Mathematial models, incorporating Fick’s diffusion law, are developed for volatilization under quiescent condition. A Theoretical model is obtained by solving a partial differential equation and is further approximated to a simplified model for practical applications. The volatilization-rate constant from this model is found to be inversely proportional to the square of the water depth instead of the thickness of liquid film multiplied by water depth used for turbulent condition. The experiments on volatilization of benzene, toluene, trichloroethylene (TCE), and tetrachloroethylene (PCE) were conducted in the laboratory. Both the theoretical model and the simplified model were applied to the experimental data, and correlation coefficients of better than 0.95 were obtained for all tested cases. However, for benzene, the dependency of volatilization-rate constant on water depth was found to be inversely proportional to the 1.81 power.